BlackBerry is working on an unannounced smartphone that has a 4.5-inch screen with a 1440 by 1440 pixel resolution, as evidenced by the latest version of the company’s SDK (software development kit).

“I know, I know...you want more details on that new device, but we’re not quite ready to give them yet, so hold tight and watch the blog for more information!,” wrote Tim Neil, director of application platform and tools product management at BlackBerry, in a blog post on Wednesday.

Neil doesn’t mention the screen’s size in his post, but he does confirm that it has 453 dots per inch, which equals 4.5 inches.

For now, BlackBerry won’t reveal any other details about the device, but with the 10.3 beta simulator developers can see how their applications will behave in the new resolution, according to Neil. His tip to developers is to check it out as soon as they can, hinting that an official announcement isn’t too far off.

Even though its sales have been catastrophically bad, BlackBerry doesn’t seem ready to give up hardware to solely focus on messaging and enterprise management software. On Thursday, the low-cost Z3 will go on sale in Indonesia. Later this year, the company will also start shipping the Classic, which has a physical QWERTY keyboard.

During the first quarter, Blackberry sold 1.3 million smartphones, down from about 6.4 million a year ago, according to ABI Research.

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